title: Enantioselective hydrolysis of dl-menthyl benzoate by cell-free extract of newly isolated Acinetobacter sp. ECU2040.
abstract: Production of l-menthol by bioprocesses attracts increasing attention nowadays. Herein, we attempted to develop a bioresolution process for production of l-menthol through enantioselective hydrolysis of dl-menthyl benzoate using a newly isolated bacterium from soil samples. Among 129 active soil isolates screened rapidly by thin-layer chromatography, an outstanding bacterial strain numbered ECU2040, which was subsequently identified as Acinetobacter species, was finally selected as our target enzyme producer due to its highest activity and the best enantioselectivity toward l-substrate as confirmed by chiral gas chromatography. The catalytic performance of the cell-free extract from Acinetobacter sp. ECU2040 was preliminarily examined, indicating that its optimal pH and temperature for the reaction were 7.5 and 37 °C, respectively. Under the optimal conditions, the enzymatic reaction was performed on a 1-L scale, affording l-menthol in 48 % yield and 71 % ee.
authors.affiliation: Laboratory of Biocatalysis and Synthetic Biotechnology, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, People's Republic of China.
authors.forename: Minh-Thu
authors.initials: MT
authors.lastname: Ngo-Thi
authors.forename: Jin-Gang
authors.initials: JG
authors.lastname: Yin
authors.forename: Jiang
authors.initials: J
authors.lastname: Pan
authors.forename: Gao-Wei
authors.initials: GW
authors.lastname: Zheng
authors.forename: Jian-He
authors.initials: JH
authors.lastname: Xu
mesh_terms: D000150:Acinetobacter / Q000737:chemistry* / Q000145:classification* / Q000302:isolation & purification; D001565:Benzoates / Q000737:chemistry*; D002474:Cell-Free System / Q000737:chemistry*; D006868:Hydrolysis; D007536:Isomerism; D008610:Menthol / Q000138:chemical synthesis*; D013045:Species Specificity
chemical_list: D001565:Benzoates; D008610:Menthol